Raster renderer that generates contours on the fly for a source raster band. More...

#include <qgsrastercontourrenderer.h>

Inheritance diagram for QgsRasterContourRenderer:

[legend]

Public Member Functions
	QgsRasterContourRenderer (const QgsRasterContourRenderer &)=delete
	QgsRasterContourRenderer cannot be copied. Use clone() instead.

	QgsRasterContourRenderer (QgsRasterInterface *input)
	Creates a contour renderer.

	~QgsRasterContourRenderer () override

QgsRasterBlock *	block (int bandNo, const QgsRectangle &extent, int width, int height, QgsRasterBlockFeedback *feedback=nullptr) override
	Read block of data using given extent and size.

QgsRasterContourRenderer *	clone () const override
	Clone itself, create deep copy.

double	contourIndexInterval () const
	Returns the interval of index contour lines (index contour lines are typical further apart and with a wider line symbol)

QgsLineSymbol *	contourIndexSymbol () const
	Returns the symbol of index contour lines.

double	contourInterval () const
	Returns the interval of contour lines generation.

QgsLineSymbol *	contourSymbol () const
	Returns the symbol used for contour lines.

QList< QgsLayerTreeModelLegendNode * >	createLegendNodes (QgsLayerTreeLayer *nodeLayer) override
	Creates a set of legend nodes representing the renderer.

double	downscale () const
	Returns by how much the renderer will scale down the request to the data provider.

Qgis::RasterRendererFlags	flags () const override
	Returns flags which dictate renderer behavior.

int	inputBand () const override
	Returns the input band for the renderer, or -1 if no input band is available.

const QgsRasterContourRenderer &	operator= (const QgsRasterContourRenderer &)=delete
	QgsRasterContourRenderer cannot be copied. Use clone() instead.

void	setContourIndexInterval (double interval)
	Sets the interval of index contour lines (index contour lines are typical further apart and with a wider line symbol)

void	setContourIndexSymbol (QgsLineSymbol *symbol)
	Sets the symbol of index contour lines.

void	setContourInterval (double interval)
	Sets the interval of contour lines generation.

void	setContourSymbol (QgsLineSymbol *symbol)
	Sets the symbol used for contour lines. Takes ownership of the passed symbol.

void	setDownscale (double scale)
	Sets by how much the renderer will scale down the request to the data provider.

bool	setInputBand (int band) override
	Attempts to set the input band for the renderer.

QList< int >	usesBands () const override
	Returns a list of band numbers used by the renderer.

void	writeXml (QDomDocument &doc, QDomElement &parentElem) const override
	Write base class members to xml.

Public Member Functions inherited from QgsRasterRenderer
	QgsRasterRenderer (const QgsRasterRenderer &)=delete
	QgsRasterRenderer cannot be copied. Use clone() instead.

	QgsRasterRenderer (QgsRasterInterface *input=nullptr, const QString &type=QString())
	Constructor for QgsRasterRenderer.

	~QgsRasterRenderer () override

virtual bool	accept (QgsStyleEntityVisitorInterface *visitor) const
	Accepts the specified symbology visitor, causing it to visit all symbols associated with the renderer.

int	alphaBand () const

int	bandCount () const override
	Gets number of bands.

virtual bool	canCreateRasterAttributeTable () const
	Returns `true` if the renderer is suitable for attribute table creation.

void	copyCommonProperties (const QgsRasterRenderer *other, bool copyMinMaxOrigin=true)
	Copies common properties like opacity / transparency data from other renderer.

Qgis::DataType	dataType (int bandNo) const override
	Returns data type for the band specified by number.

virtual QList< QPair< QString, QColor > >	legendSymbologyItems () const
	Returns symbology items if provided by renderer.

const QgsRasterMinMaxOrigin &	minMaxOrigin () const
	Returns const reference to origin of min/max values.

bool	needsRefresh (const QgsRectangle &extent) const
	Checks if the renderer needs to be refreshed according to extent.

QColor	nodataColor () const
	Returns the color to use for shading nodata pixels.

double	opacity () const
	Returns the opacity for the renderer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque).

const QgsRasterRenderer &	operator= (const QgsRasterRenderer &)=delete
	QgsRasterRenderer cannot be copied. Use clone() instead.

const QgsRasterTransparency *	rasterTransparency () const

void	readXml (const QDomElement &rendererElem) override
	Sets base class members from xml. Usually called from create() methods of subclasses.

virtual bool	refresh (const QgsRectangle &extent, const QList< double > &min, const QList< double > &max, bool forceRefresh=false)
	Refreshes the renderer according to the min and max values associated with the extent.

void	setAlphaBand (int band)

bool	setInput (QgsRasterInterface *input) override
	Set input.

void	setMinMaxOrigin (const QgsRasterMinMaxOrigin &origin)
	Sets origin of min/max values.

void	setNodataColor (const QColor &color)
	Sets the color to use for shading nodata pixels.

void	setOpacity (double opacity)
	Sets the opacity for the renderer, where opacity is a value between 0 (totally transparent) and 1.0 (fully opaque).

void	setRasterTransparency (QgsRasterTransparency *t)

virtual void	toSld (QDomDocument &doc, QDomElement &element, const QVariantMap &props=QVariantMap()) const
	Used from subclasses to create SLD Rule elements following SLD v1.0 specs.

virtual QString	type () const
	Returns a unique string representation of the renderer type.

bool	usesTransparency () const

Public Member Functions inherited from QgsRasterInterface
	QgsRasterInterface (QgsRasterInterface *input=nullptr)

virtual	~QgsRasterInterface ()=default

Q_DECL_DEPRECATED QgsRasterBandStats	bandStatistics (int bandNo, int stats, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, QgsRasterBlockFeedback *feedback=nullptr)
	Returns the band statistics.

virtual QgsRasterBandStats	bandStatistics (int bandNo, Qgis::RasterBandStatistics stats=Qgis::RasterBandStatistic::All, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, QgsRasterBlockFeedback *feedback=nullptr)
	Returns the band statistics.

virtual Qgis::RasterInterfaceCapabilities	capabilities () const
	Returns the capabilities supported by the interface.

Q_DECL_DEPRECATED QString	capabilitiesString () const
	Returns the raster interface capabilities in friendly format.

virtual QString	colorInterpretationName (int bandNumber) const
	Returns the name of the color interpretation for the specified bandNumber.

virtual void	cumulativeCut (int bandNo, double lowerCount, double upperCount, double &lowerValue, double &upperValue, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0)
	Find values for cumulative pixel count cut.

int	dataTypeSize (int bandNo) const
	Returns the size (in bytes) for the data type for the specified band.

QString	displayBandName (int bandNumber) const
	Generates a friendly, descriptive name for the specified bandNumber.

virtual QgsRectangle	extent () const
	Gets the extent of the interface.

virtual QString	generateBandName (int bandNumber) const
	helper function to create zero padded band names

virtual bool	hasHistogram (int bandNo, int binCount, double minimum=std::numeric_limits< double >::quiet_NaN(), double maximum=std::numeric_limits< double >::quiet_NaN(), const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, bool includeOutOfRange=false)
	Returns `true` if histogram is available (cached, already calculated)

Q_DECL_DEPRECATED bool	hasStatistics (int bandNo, int stats, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0)
	Returns `true` if histogram is available (cached, already calculated).

virtual bool	hasStatistics (int bandNo, Qgis::RasterBandStatistics stats=Qgis::RasterBandStatistic::All, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0)
	Returns `true` if histogram is available (cached, already calculated).

virtual QgsRasterHistogram	histogram (int bandNo, int binCount=0, double minimum=std::numeric_limits< double >::quiet_NaN(), double maximum=std::numeric_limits< double >::quiet_NaN(), const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, bool includeOutOfRange=false, QgsRasterBlockFeedback *feedback=nullptr)
	Returns a band histogram.

virtual QgsRasterInterface *	input () const
	Current input.

virtual bool	on () const
	Returns whether the interface is on or off.

virtual void	setOn (bool on)
	Sets whether the interface is on or off.

virtual Qgis::DataType	sourceDataType (int bandNo) const
	Returns source data type for the band specified by number, source data type may be shorter than dataType.

virtual QgsRasterInterface *	sourceInput ()
	Gets source / raw input, the first in pipe, usually provider.

virtual const QgsRasterInterface *	sourceInput () const
	Gets source / raw input, the first in pipe, usually provider.

virtual int	xBlockSize () const
	Gets block size.

virtual int	xSize () const
	Gets raster size.

virtual int	yBlockSize () const

virtual int	ySize () const

Static Public Member Functions
static QgsRasterRenderer *	create (const QDomElement &elem, QgsRasterInterface *input)
	Creates an instance of the renderer based on definition from XML (used by renderer registry)

Additional Inherited Members
Static Public Attributes inherited from QgsRasterRenderer
static const QRgb	NODATA_COLOR = qRgba( 0, 0, 0, 0 )

Protected Member Functions inherited from QgsRasterRenderer
void	_writeXml (QDomDocument &doc, QDomElement &rasterRendererElem) const
	Write upper class info into rasterrenderer element (called by writeXml method of subclasses)

QRgb	renderColorForNodataPixel () const
	Returns the color for the renderer to use to represent nodata pixels.

Protected Member Functions inherited from QgsRasterInterface
void	initHistogram (QgsRasterHistogram &histogram, int bandNo, int binCount, double minimum=std::numeric_limits< double >::quiet_NaN(), double maximum=std::numeric_limits< double >::quiet_NaN(), const QgsRectangle &boundingBox=QgsRectangle(), int sampleSize=0, bool includeOutOfRange=false)
	Fill in histogram defaults if not specified.

Q_DECL_DEPRECATED void	initStatistics (QgsRasterBandStats &statistics, int bandNo, int stats, const QgsRectangle &boundingBox=QgsRectangle(), int binCount=0) const
	Fill in statistics defaults if not specified.

void	initStatistics (QgsRasterBandStats &statistics, int bandNo, Qgis::RasterBandStatistics stats=Qgis::RasterBandStatistic::All, const QgsRectangle &boundingBox=QgsRectangle(), int binCount=0) const
	Fill in statistics defaults if not specified.

Protected Attributes inherited from QgsRasterRenderer
int	mAlphaBand = -1
	Read alpha value from band.

QgsRectangle	mLastRectangleUsedByRefreshContrastEnhancementIfNeeded
	To save computations and possible infinite cycle of notifications.

QgsRasterMinMaxOrigin	mMinMaxOrigin
	Origin of min/max values.

double	mOpacity = 1.0
	Global alpha value (0-1)

QgsRasterTransparency *	mRasterTransparency = nullptr
	Raster transparency per color or value. Overwrites global alpha value.

QString	mType

Protected Attributes inherited from QgsRasterInterface
QList< QgsRasterHistogram >	mHistograms
	List of cached histograms, all bands mixed.

QgsRasterInterface *	mInput = nullptr

bool	mOn = true

QList< QgsRasterBandStats >	mStatistics
	List of cached statistics, all bands mixed.

Detailed Description

Raster renderer that generates contours on the fly for a source raster band.

Since: QGIS 3.14

Definition at line 30 of file qgsrastercontourrenderer.h.

Constructor & Destructor Documentation

◆ QgsRasterContourRenderer() [1/2]

QgsRasterContourRenderer::QgsRasterContourRenderer ( QgsRasterInterface * input )

explicit

Creates a contour renderer.

Definition at line 25 of file qgsrastercontourrenderer.cpp.

◆ ~QgsRasterContourRenderer()

QgsRasterContourRenderer::~QgsRasterContourRenderer ( )

overridedefault

◆ QgsRasterContourRenderer() [2/2]

QgsRasterContourRenderer::QgsRasterContourRenderer ( const QgsRasterContourRenderer & )

delete

QgsRasterContourRenderer cannot be copied. Use clone() instead.

Member Function Documentation

◆ block()

QgsRasterBlock * QgsRasterContourRenderer::block	(	int	bandNo,
		const QgsRectangle &	extent,
		int	width,
		int	height,
		QgsRasterBlockFeedback *	feedback = `nullptr`
	)

overridevirtual

Read block of data using given extent and size.

Returns pointer to data. Caller is responsible to free the memory returned.

Parameters

bandNo	band number
extent	extent of block
width	pixel width of block
height	pixel height of block
feedback	optional raster feedback object for cancellation/preview. Added in QGIS 3.0.

Implements QgsRasterRenderer.

Definition at line 144 of file qgsrastercontourrenderer.cpp.

◆ clone()

QgsRasterContourRenderer * QgsRasterContourRenderer::clone ( ) const

overridevirtual

Clone itself, create deep copy.

Implements QgsRasterRenderer.

Definition at line 33 of file qgsrastercontourrenderer.cpp.

◆ contourIndexInterval()

double QgsRasterContourRenderer::contourIndexInterval ( ) const

inline

Returns the interval of index contour lines (index contour lines are typical further apart and with a wider line symbol)

Definition at line 68 of file qgsrastercontourrenderer.h.

◆ contourIndexSymbol()

QgsLineSymbol * QgsRasterContourRenderer::contourIndexSymbol ( ) const

inline

Returns the symbol of index contour lines.

Definition at line 73 of file qgsrastercontourrenderer.h.

◆ contourInterval()

double QgsRasterContourRenderer::contourInterval ( ) const

inline

Returns the interval of contour lines generation.

Definition at line 58 of file qgsrastercontourrenderer.h.

◆ contourSymbol()

QgsLineSymbol * QgsRasterContourRenderer::contourSymbol ( ) const

inline

Returns the symbol used for contour lines.

Definition at line 63 of file qgsrastercontourrenderer.h.

◆ create()

QgsRasterRenderer * QgsRasterContourRenderer::create	(	const QDomElement &	elem,
		QgsRasterInterface *	input
	)

static

Creates an instance of the renderer based on definition from XML (used by renderer registry)

Definition at line 51 of file qgsrastercontourrenderer.cpp.

◆ createLegendNodes()

QList< QgsLayerTreeModelLegendNode * > QgsRasterContourRenderer::createLegendNodes ( QgsLayerTreeLayer * nodeLayer )

overridevirtual

Creates a set of legend nodes representing the renderer.

The default implementation calls legendSymbologyItems() and creates corresponding legend nodes for each returned symbology item.

Subclasses can override this to return more legend nodes which better represent the renderer.

Since: QGIS 3.18

Reimplemented from QgsRasterRenderer.

Definition at line 224 of file qgsrastercontourrenderer.cpp.

◆ downscale()

double QgsRasterContourRenderer::downscale ( ) const

inline

Returns by how much the renderer will scale down the request to the data provider.

For example, for a raster block 1000x500 with downscale 10, the renderer will request raster 100x50 from provider. Higher downscale makes contour lines more simplified (at the expense of losing some detail). The value of one means there will be no downscaling.

Definition at line 83 of file qgsrastercontourrenderer.h.

◆ flags()

Qgis::RasterRendererFlags QgsRasterContourRenderer::flags ( ) const

overridevirtual

Returns flags which dictate renderer behavior.

Since: QGIS 3.28

Reimplemented from QgsRasterRenderer.

Definition at line 46 of file qgsrastercontourrenderer.cpp.

◆ inputBand()

int QgsRasterContourRenderer::inputBand ( ) const

overridevirtual

Returns the input band for the renderer, or -1 if no input band is available.

For renderers which utilize multiple input bands -1 will be returned. In these cases usesBands() will return a list of all utilized bands (including alpha bands).

See also: setInputBand(); usesBands()

Since: QGIS 3.38

Reimplemented from QgsRasterRenderer.

Definition at line 240 of file qgsrastercontourrenderer.cpp.

◆ operator=()

const QgsRasterContourRenderer & QgsRasterContourRenderer::operator= ( const QgsRasterContourRenderer & )

delete

QgsRasterContourRenderer cannot be copied. Use clone() instead.

◆ setContourIndexInterval()

void QgsRasterContourRenderer::setContourIndexInterval ( double interval )

inline

Sets the interval of index contour lines (index contour lines are typical further apart and with a wider line symbol)

Definition at line 70 of file qgsrastercontourrenderer.h.

◆ setContourIndexSymbol()

void QgsRasterContourRenderer::setContourIndexSymbol ( QgsLineSymbol * symbol )

Sets the symbol of index contour lines.

Definition at line 265 of file qgsrastercontourrenderer.cpp.

◆ setContourInterval()

void QgsRasterContourRenderer::setContourInterval ( double interval )

inline

Sets the interval of contour lines generation.

Definition at line 60 of file qgsrastercontourrenderer.h.

◆ setContourSymbol()

void QgsRasterContourRenderer::setContourSymbol ( QgsLineSymbol * symbol )

Sets the symbol used for contour lines. Takes ownership of the passed symbol.

Definition at line 260 of file qgsrastercontourrenderer.cpp.

◆ setDownscale()

void QgsRasterContourRenderer::setDownscale ( double scale )

inline

Sets by how much the renderer will scale down the request to the data provider.

See also: downscale()

Definition at line 89 of file qgsrastercontourrenderer.h.

◆ setInputBand()

bool QgsRasterContourRenderer::setInputBand ( int band )

overridevirtual

Attempts to set the input band for the renderer.

Returns true if the band was successfully set, or false if the band could not be set.

Note: Not all renderers support setting the input band.

See also: inputBand(); usesBands()

Since: QGIS 3.38

Reimplemented from QgsRasterRenderer.

Definition at line 245 of file qgsrastercontourrenderer.cpp.

◆ usesBands()

QList< int > QgsRasterContourRenderer::usesBands ( ) const

overridevirtual

Returns a list of band numbers used by the renderer.

See also: setInputBand()

Reimplemented from QgsRasterRenderer.

Definition at line 214 of file qgsrastercontourrenderer.cpp.

◆ writeXml()

void QgsRasterContourRenderer::writeXml	(	QDomDocument &	doc,
		QDomElement &	parentElem
	)		const

overridevirtual

Write base class members to xml.

Reimplemented from QgsRasterInterface.

Definition at line 91 of file qgsrastercontourrenderer.cpp.

The documentation for this class was generated from the following files:

/build/qgis-3.41.0+git20241214+cea29feecf2+99sid/src/core/raster/qgsrastercontourrenderer.h
/build/qgis-3.41.0+git20241214+cea29feecf2+99sid/src/core/raster/qgsrastercontourrenderer.cpp

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsRasterContourRenderer() [1/2]

◆ ~QgsRasterContourRenderer()

◆ QgsRasterContourRenderer() [2/2]

Member Function Documentation

◆ block()

◆ clone()

◆ contourIndexInterval()

◆ contourIndexSymbol()

◆ contourInterval()

◆ contourSymbol()

◆ create()

◆ createLegendNodes()

◆ downscale()

◆ flags()

◆ inputBand()

◆ operator=()

◆ setContourIndexInterval()

◆ setContourIndexSymbol()

◆ setContourInterval()

◆ setContourSymbol()

◆ setDownscale()

◆ setInputBand()

◆ usesBands()

◆ writeXml()